Gold LayersWilliam F. ColemanFour spheres surrounding a tetrahedral hole and six spheres surrounding an octahedral hole are highlighted and are partially transparent to show the holes.

Crystals / Crystallography |

Metals |

Solids |

Enrichment / Review Materials

3D Molecular Symmetry Shockwave; A Web Application for Interactive VisualizationNickolas D. Charistos, Constantinos A. Tsipis, Michail P. Sigalas3D Molecular Symmetry Shockwave is a Web-based application for interactive visualization and three-dimensional perception of molecular symmetry. The user interface is simple, and students learn how to use the program from the built-in help screens. The animation uses the Macromedia Shockwave browser plug-in, and requires a download of only 256 KB, allowing it to be used even with low bandwidth Internet connections. Its performance is comparable to a desktop application.

Crystals / Crystallography |

Group Theory / Symmetry |

Molecular Properties / Structure |

Thermodynamics

Close Packing of Layers of SpheresWilliam F. ColemanAn animation of the close packing of layers of spheres. In this version, clicking on text links adds the second and third layers, with two options for the third layer. After both ways of adding the third layer have been explored the user has an option to go to a second version that has no text but rather allows the user to drag the layers over one another.

Crystals / Crystallography |

Molecular Properties / Structure |

Solids |

Enrichment / Review Materials

Lattice EnergyWilliam F. ColemanPowerPoint presentation covering various aspects of the concept of lattice energy at the introductory and intermediate inorganic chemistry level. The presentation will open directly in the browser if your system has been so configured.

Crystals / Crystallography |

Ionic Bonding |

Solids |

Enrichment / Review Materials

Radius RatioWilliam F. ColemanThis is a set of animations that demonstrates properties of the spherical holes formed when uniform spheres are packed. Cubic, octahedral and tetrahedral packing arrangements may be examined without anything in the holes,and with the repective holes filled. The sizes of the various holes relative to the spheres being packed are shown, which can lead students into an exploration of the radius ratio concept. An example is given of computing the relative size of an octahedral hole.

Crystals / Crystallography |

Ionic Bonding |

Solids |

Enrichment / Review Materials

An Animated Interactive Overview of Molecular SymmetryMarion E. Cass, Henry S. Rzepa, David R. Rzepa, Charlotte K. WilliamsAn Animated Interactive Overview of Molecular Symmetry is a series of Web pages designed to help instructors teach molecular symmetry. These pages combine interactive Jmol images and instructional text that allow students to examine and explore the operations and elements that give rise to molecular symmetry.

Crystals / Crystallography |

Group Theory / Symmetry |

Molecular Properties / Structure |

Thermodynamics

HCP LayersWilliam F. ColemanAn animation showing both the top and side views when three layers of spheres are arranged in a hexagonal close-packed array The user can control the animation through vcr controls.

Crystals / Crystallography |

Molecular Properties / Structure |

Solids |

Enrichment / Review Materials

Mage; A Tool for Developing Interactive Instructional GraphicsStephen F. PavkovicMage is a graphics program especially well suited for visualizing three-dimensional structures of proteins and other macromolecules. It is an important tool for biochemists and finds many applications in biochemistry courses. We utilize Mage to create interactive instructional graphics of potential use in a wider range of undergraduate chemistry courses, and present some of those applications here.

Crystals / Crystallography |

Group Theory / Symmetry |

VSEPR Theory |

Molecular Properties / Structure |

Stereochemistry |

Proteins / Peptides

Characteristics of MaterialsAmerican Chemical SocietyWhat makes diapers absorbent? Is peanut butter stickier than syrup or jelly? Strong, stretchy, sticky, or sweet—everything around us has special properties which make them unique. See if you can identify and compare the characteristics of materials.